高盐水热改性凹凸棒石对Cu的吸附和钝化性能  

Study on the Adsorption and Passivation of Cu by Hydrothermally Modified Attapulgite under High Salinity Condition

作　　者：马贵[1,2] 任珺 陶玲 韩新宁[4] 周悦 廖彩云[4] Ma Gui;Ren Jun;Tao Ling;Han Xinning;Zhou Yue;Liao Caiyun(Key laboratory of Yellow River Water Environment in Gansu Province,Lanzhou Jiaotong University,Lanzhou,Gansu 730070;School of Environmental and Municipal Engineering,Lanzhou Jiaotong University,Gansu,Lanzhou 730070;Gansu Hanxing Environmental Protection Co.,Ltd.,Gansu,Lanzhou 730070;College of Resources,Environment and Life Sciences,Ningxia Normal University,Guyuan,Ningxia 756000)

机构地区：[1]兰州交通大学甘肃省黄河水环境重点实验室,甘肃兰州730070 [2]兰州交通大学环境与市政工程学院,环境生态研究所,甘肃兰州730070 [3]甘肃瀚兴环保科技有限公司,甘肃兰州730070 [4]宁夏师范学院资源环境与生命科学学院,宁夏固原756200

出　　处：《非金属矿》2023年第1期60-65,共6页Non-Metallic Mines

基　　金：甘肃省教育厅产业支撑计划项目(2021CYZC-31);甘肃省科技厅科技计划项目(22CX3GA076);兰州市人才创新创业项目(2021-RC-41);甘肃省优秀研究生“创新之星”项目(2022CXZX-514);宁夏回族自治区重点研发计划项目(2021BEE03019)。

摘　　要：采用高盐水(模拟海水)对低品位凹凸棒石进行水热改性,并利用扫描电镜(SEM)、X射线衍射(XRD)和傅里叶红外光谱(FTIR)对改性前后的凹凸棒石进行表征,同时探讨改性后的凹凸棒石对水和土壤中Cu吸附和钝化效果。结果表明,高盐水热改性使凹凸棒石棒状晶体减少、变短,片状和颗粒状物质增多;凹凸棒石转变为石英和长石。高盐水热改性凹凸棒石对水中Cu2+的吸附率增加13.45%~23.35%,其吸附过程符合拟二级动力学模型和Freundlich模型,是物理和化学相复合的不均匀多层吸附过程,受表面扩散和颗粒内扩散控制。添加高盐水热改性后的凹凸棒石能显著提高土壤pH值、电导率(EC)和阳离子交换容量(CEC),降低土壤中DTPA-Cu和TCLP-Cu含量,并使土壤中Cu由酸溶态向残渣态转化。高盐水热改性能提高低品位凹凸棒石对水和土壤中铜的吸附及钝化能力,具有规模化应用于Cu污染修复的潜力。In this paper,low-grade attapulgite was hydrothermally modified with high salt water(simulated seawater).The attapulgite before and after modification were characterized by SEM,XRD and FTIR.The adsorption and passivation effects of modified attapulgite on Cu in water and soil were analyzed.The results show that hydrothermal modification under high salt conditions reduces the number of attapulgite rod-shaped crystals and shortens the rod body,but increases the flaky and granular materials,and attapulgite transforms into silica and feldspar.The adsorption rate of attapulgite for Cu2+in water increases by 13.45%-23.35%after thermal modification of high salt water.The adsorption process conforms to the Freundlich model and the pseudo-second-order kinetic model.It is a heterogeneous multi-layered complex of physical and chemical phases.The adsorption process is controlled by surface diffusion and intraparticle diffusion.The addition of modified attapulgite can significantly increase soil pH,EC and CEC,reduce the content of DTPA-Cu and TCLP-Cu in soil,and convert Cu from acid-soluble state to residue state in soil.Hydrothermal modification under high salt conditions can improve the adsorption and passivation ability of low-grade attapulgite to copper in water and soil,respectively,and has the potential of large-scale application in Cu pollution remediation.

关 键 词：海水 凹凸棒石 水热 CU 吸附 钝化 

分 类 号：TB321[一般工业技术—材料科学与工程] X53[环境科学与工程—环境工程]